Couplings, or coupler, are commonly used in a variety of motion control applications, from aviation and laboratory equipment to robotics, and medical devices. A coupling is a mechanical element that connects two shafts together to transmit power and movement. Couplers can be flexible or rigid.
There are many different coupling types, shapes and sizes, the right choice of coupler will be dependent upon your applications and specifications.
When deciding which shaft coupler is best, many considerations need to be factored in to ensure the correct coupling is used to reduce instances of coupler failure, improve system capability, and reduce system issues.
Rigid couplings are used where precise alignment is of paramount as there is no movement between the shafts with this coupler type.
Flexible couplings are used where a degree of motion is needed between the shafts. These couplings can improve the performance of a machine and reduce wear and tear. They are easy to install and have a long-life span. The types of couplings that sit within the flexible couplings area are gear couplings, Oldham couplings and universal joint couplings.
Gear couplings are flexible and capable of high torque transmission between shafts that are not collinear, because of this they are frequently use on large industrial machinery where high power applications are needed.
Bellow couplings can accommodate all forms of misalignment and have a balanced design for reduced vibration at high speeds. They are best suited for applications where precise positioning is required, such as in material handling or general automation and assembly.
Oldham couplings are used to connect parallel shafts that are slightly out of line, this kind of parallel misalignment can occur where power transmission is needed at different elevations. The Oldham coupling consists of three discs, connected to either side of the drive, and the third sandwiched in between.
Jaw couplings are made from flexible materials. Due to this, they can accommodate any misalignment caused by thermal expansion or manufacturing inefficiencies and are usually found in lower power transmission applications such as the electrical motor and internal combustion systems. They work by preventing shock loading, the sudden and drastic increase of load in a system."